Process for producing 1,1,2-trichloroethane

Abstract

The present disclosure relates to a process for producing 1,1,2-trichloroethane. According to the present disclosure, a process for producing 1,1,2-trichloroethane with a simplified equipment and a high reaction yield is provided.

Claims

1. A process for producing 1,1,2-trichloroethane, comprising a step of obtaining a product containing 1,1,2-trichloroethane by an addition reaction of a dissolved vinyl chloride monomer and dissolved chlorine in contact with each other under a liquid medium comprising a chlorinated hydrocarbon-based solvent and iron(III) chloride as a catalyst suspended therein, wherein the step is carried out in a reaction unit comprising a gas-lift type of bubble column through which the liquid medium is circulated without a separate pump by gas containing the dissolved vinyl chloride monomer and dissolved chlorine and an external down-comer which circulates the gas and liquid medium out of the bubble column, wherein the addition reaction takes place in both the bubble column and the external down-corner, wherein the vinyl chloride monomer and chlorine are respectively supplied to a section in which the liquid medium rises in the gas-lift type of bubble column, wherein the step is carried out at a reaction temperature of 25 to 80° C.

2. The process for producing 1,1,2-trichloroethane of claim 1, wherein the chlorinated hydrocarbon-based solvent comprises at least one compound selected from the group consisting of carbon tetrachloride, chloroform, 1,2-dichloroethane, methylene chloride, trichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, and tetrachloroethylene.

3. The process for producing 1,1,2-trichloroethane of claim 1, wherein the catalyst comprises 100 to 1000 ppm of iron(III) chloride.

4. The process for producing 1,1,2-trichloroethane of claim 1, wherein a volumetric flow ratio of vinyl chloride monomer to chlorine ranges 1:1 to 1:0.8.

5. The process for producing 1,1,2-trichloroethane of claim 1, further comprising a step of recovering 1,1,2-trichloroethane by distilling the product containing 1,1,2-trichloroethane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 schematically shows an example of a reaction unit used in the process for producing 1,1,2-trichloroethane according to an embodiment of the present disclosure.

(2) FIG. 2 schematically shows another example of a reaction unit used in the process for producing 1,1,2-trichloroethane according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(3) Hereinafter, preferable examples and comparative examples are presented for better understanding the present invention. However, the following examples are only for illustrating the present invention and the present invention is not limited to or by them.

Example

(4) A gas-lift type of bubble column (capacity 20 L) equipped with an external down-corner as shown in FIG. 1 was prepared.

(5) About 16.5 L of 1,2-dichloroethane, which is a liquid medium, and 100 ppm of iron(III) chloride were added to the bubble column and the external down-corner.

(6) The vinyl chloride monomer and chlorine were continuously supplied at 8 SLPM, respectively, through two nozzles provided in the section in which the liquid medium rose in the external down-corner. The continuous supply circulated the liquid medium at a rate of 4 L/min and chlorination of the vinyl chloride monomer proceeded. The reaction was carried out continuously under the conditions of 40° C. and 1 bar.

Test Example

(7) While performing the reaction according to the above example, a product was collected at hourly intervals from 3 hours to 8 hours after the initiation of the reaction. At this time, the product was taken from the top (front; where descending of liquid medium begins) and the bottom (rear; where descending of liquid medium ends) of the external down-corner, respectively.

(8) A concentration (mol/L) of 1,1,2-trichloroethane contained in each of the products collected was measured and is shown in Table 1 below.

(9) TABLE-US-00001 TABLE 1 Concentration of 1,1,2-trichloroethane (mol/L) Down-comer 3 hours 4 hours 5 hours 6 hours 7 hours 8 hours Top 2.24 2.91 3.25 3.78 4.21 4.58 Bottom 2.26 2.94 3.44 4.01 4.44 4.77

(10) Referring to Table 1, the concentration of 1,1,2-trichloroethane was higher in the sample collected at the bottom (rear) than the sample collected at the top (front) of the external down-corner over time. As a result, it was confirmed that sufficient contact and residence time may be secured while passing through the external down-corner to allow the chlorination of the vinyl chloride monomer, and thus continuous chlorination is possible.

DESCRIPTION OF SYMBOLS

(11) TABLE-US-00002 100: Reaction unit  10: Gas-lift type of bubble column  20: External down-comer 150: Distillation column